Closure



A. F. HULSE Nov. 7, 1939.

CLOSURE Original Filed Oct. 12. 1936 v INVENTOR TORNEY Patented Nov. 7, 1939 2,178,964 a I I.

GLO SURE Refiled for abandoned application Serial No.

105.223, October 12, 1936.

This application March 3, 1939, Serial No. 25$,Gil9

4 Claims. (c1. 220-57) This application is a substitute for application Serial Number 105,223, filed October 12, 1936.

This invention relates, broadly, to removable closures; more specifically to closures or covers 6 for receptacles; and it has to do especially with a mechanical arrangement for tightly securing a. cover on a receptacle while permitting it easily to be removed'as the need arises, and quickly and easily replaced.

l My invention, though described with reference to a receptacle, is not so restricted in its utility and scope. It may be employed advantageously in any appropriate situation involving an opening requiring a removable closure whether the opening be in a receptacle or otherwise.

The present invention was conceived and is herein described as a component part of an airoperated spray gunthe receptacle being employed to hold paint or other fluid to be sprayedbut, as will be self-evident, the utility of the invention is not limited to the spray gun art.

In a spray gun of the type comprising (as an integral part) a fluid receptacle, it is essential that the receptacle be readily and quickly removable for cleaning and refilling; and replaceable with equal facility. There must be a sufficiently tight seal between the receptacle audits cover (i. e., the part of the gun to which the receptacle is attached) to ensure against'leakage; and this is accomplished most conveniently by means of a gasketgenerally a rubber gasket and a suitable clamping or securing device.

Heretofore, it has been the practice of at least some spray gun manufacturers to use a cam to operate the clamping device for tightly closing the gasketed jointsealing pressure being applied by the cam. Such an arrangement works very well when the sealing gasket is new; but, in the course of time, as the gasket becomes compressed, it is necessary to move the cam an everincreasing amount in order to efiect a tight closure.

The degreeto which the cam must be rotated in order to effect a tight closure when the gasket has become compressed would not be of any material consequence were it not for the fact that a cam requiring so much rotation to be eifective does not lend itself well to the surrounding conditions. That is to say, such a cam does not permit ofthe clamping mechanism, as a whole, being as simple, compact and inexpensive as is desirable.

The present invention has for its object to provide a receptacle closure .clamping mechanism of neat, compact and inexpensive design wherein the above-described deficiency of prior art clamping mechanisms is avoided.

My invention is characterized in that the clampingv pressure is applied-not by a cam but by a spring-a cam or its mechanical equivalent gifi being employed to release the clamping pressure instead of applying it. With such an arrangement, a given amount of cam movement operatesto release the receptacle without regard to the condition of the gasket; and the spring whichr functions to apply the necessary clamping pressure is amply eiiective whether the gasket be new or old.

In the drawing which accompaniesthis specification I have depicted my invention as appliedeto a spray gun; but'it is to be borne inmind that the spray gun illustrates only one of the anism is shown in its closed or clamping position of operation, the cover being tightly secured to thereceptacle.

Fig. 3 is identical with Fig. 2 except that the ,clamping mechanism is shown in its open or re ;35

leased position of operation.

As hereshown the fluid receptacle can easily be withdrawn from the a gun for refilling or cleaning.

.Fig. 4 is a vertical section taken along the line l4 of Fig. 2. 40

Fig. 5 is a plan view of the fluid receptacle,

cover and clamping mechanism taken along the line 5--5 of Fig. 2. i v

Since the invention herein claimed lies entirely in the clamping mechanism for detachably se- 45 curing together the fluid receptacle and its cover, it is unnecessary to describe the entire spray gun beyond stating that it comprises a spraynozzle' I, a handle 2 and an operating trigger 3., i 1

A receptacle t contains the paint or other ma 5o terial to be sprayed and, in operation, must frequently be removed for refilling or cleaning; as the case may be. It is provided with a. large opening at. the top as clearly shown in Fig. 4. I

Extending downwardly from the spray nozzle 1 55 is a feed pipe through which the material to be sprayed is conducted from receptacle 6 to the nozzle. The feed-pipe consists of three articulated lengths 5, 6 and 7!, respectively, separately joined end-to-end by screw couplings 8 and 9.

A. closure in the form of a lid or cover l0, provided with an annular rubber gasket I i, is firmly secured to portion 6 of the feed-pipe by being threaded thereon as illustrated in Fig. 5. The

cover serves to close the opening in the receptacle and the rubber gasket functions to seal the joint therebetwe'en against leakage.

Substantial pressure is required to be applied to the gasketed joint to ensure against leakage 5 and, in time, the gasket becomes compressed or worn; and it follows that, if a cam is used to apply the necessary pressure, it becomes necessary to turn the cam an ever-increasing amount to compensate for the diminished thickness of the gasket; and that factor I have found to be inimical to an entirely satisfactory mechanical design.

The clamping mechanism illustrated and which presently will be described is devoid of the aboveindicated deficiencythe desired result being accomplished by causing the pressure upon the joint to be exerted by a strong spring instead of by a carnwhich spring exerts nearly as much pressure on the joint when the gasket has become thin as when it is newa cam being employed to release the pressure on the jointwhich is the converse of prior practice.

The clamping mechanism includes a multiplearm bridge member l2 which, in the present instance, has two diametrically opposed arms l3 and M, each arm having a hook at its extremity (see Fig. 1) which is adapted to engage a trunnion (l5 and I5) attached to and extending outwardly from the upper portion of the receptacle.

"4 Bridge member H has a central hub with an axial opening through which passes portion 6 of the feed-pipe, the bridge member being slidable up and down on the feed-pipe.

Encircling the feed-pipe and interposed be- -4 tween the top of cover It] and the under side annular member l8 having oppositely disposed arcuate notches l9 (see Fig. 2) only one notch being shown in the drawing. Between the annular member l8 and coupling 8 is a cam 20 having a pair of oppositely disposed arcuate risers or protuberances 2| which are normally seated in notches l9, see Fig. 2. Cam 20 is provided with a lever 22 by means of which it can be rotated about the feed-pipe as a center of rotation. When the cam is so rotated fromv the position shown in Fig. 2; protuberances 2| are disengaged from notches l9 andbridge member I2 is forced downwardly against the pressure of spring IT. The pressure between the receptacle and its cover is thus relieved and the receptacle can then easily be withdrawn, a slight twist to disengage the hooks from the trunnions being required. Figs. 2 and 3 show the mechanism in clamping and released positions of operation respectively. I'n'Fig. 5 the cam lever 22 is shown in full lines in the clamping position and in dotted lines in the released position.

It will be observed that in the structure illustrated and described the feed-pipe serves two purposes; that is, it functions as a feed-pipe and 5 also as a shaft or stem upon which the several parts of the clamping mechanism are assembled; and as a tension member for transmitting the force exerted by the cam. So far as the operation of the clamping mechanism is concerned, it is 10 wholly immaterial that the shaft or stem is hollow and functions as a conduit for the material to be sprayed. Obviously, the stem could be solid, and preferably so, when the invention is employed under circumstances not requiring a con- 15 duit therethrough. 1

The design and adjustment of the mechanism is preferably such as to provide considerable clearance between the cam and the member 18 and between the cam and coupling 8 when the 20 cam is in the position shown in Fig. 2, the clamping position. This clearance is necessary in order that the bridge member may be free to pull up tightly on the trunnions and also to com pensate for thinning of the gasket. 25

What is claimed is:

1. The combination with structure defining an opening, of a removable closure for said opening, a stem attached to and protruding from said closure, a member bridging said closure and de- 30 tachably connected to said structure, a spring encircling said stem, said spring being interposed between and pressing oppositely against said closure and said membenand manually operable means mounted on said stem and rotatable there-3 5 about for compressing said spring.

2. The combination with structure defining an opening, of a removable closure for said opening, a stem attached to and protruding from said closure, a clamping member bridging said olesure and detachably connected to said structure, said member having an apertured hub through which said stem projects, a helical spring encircling said stem, said spring being interposed between and pressing oppositely against said 010- :45 sure and said member, a cam mounted on said stem, said cam engaging said member on the side thereof opposite said spring, said cam being rotatable about said stem as a center of rotation.

3. The combination with a receptacle havingi50 an opening, of a removable closure for said opening, a pair of trunnions attached to said receptacle at opposite sides of said opening, a stem attached and protruding outwardly from the center of said closure, a bridging member having an 5 aperture at its center through which said stem projects, said bridging member having a pair of oppositely disposed arms, each of which arms is provided at its extremity with a hook adapted to engage said trunnions individually, a spring encircling said stem, said spring being interposed between and pressing oppositely against said closure and said member, and a manually operable cam encircling said stem, said cam being operative to move said member toward said closure in .65 opposition to said spring,.thereby releasing said closure and permitting its withdrawal from said opening.

4. In combination, a fluid receptacle having an opening, a removable cover for said opening, a t'l) fiuid ccnduit'extending from the interior of said receptaclethrough said cover and projecting exteriorly thereof, said conduit being attached to said cover and removable therewith from said receptacle, a member slidably mounted on said con- 75 cover tightly in place with respect to said opening, and a manually operable cam encirclingsaid conduit, said cam being operative to compress said spring and thereby to release the connection between said member and said receptacle 5 and thus permit removal of said cover. ARTHUR F. HULSE. 

